Does moderate tea drinking cause iron deficiency?

Answered by: Dr Shirish Kumar | Haematologist, WHO, Geneva

Q:I have come to know recently that I am anaemic and the doctor has prescribed some iron tablets. I want to know whether consumption of tea hinders the absorption of iron in the blood. I drink atmost 3 cup of tea in a day. Is it safe?

A:Iron has several vital functions in the body, its major role being as a carrier of oxygen in blood haemoglobin and muscle myoglobin. It is also a component of many enzymes and is required for a number of metabolic processes.
Dietary iron is available in two valency states, Fe 2+ (ferrous) and Fe 3+ (ferric). The majority of ferrous form is found in haeme iron (as haemoglobin & myoglobin in meat and meat products) while most ferric iron is found in non-haeme iron (plant foods like cereals, vegetables, pulses, dried fruits etc.)
Haeme iron is readily available and ususally 20-30% of it is absorbed from the diet. This can increase upto 40% when an individual is iron deficient. The level of haeme iron absorption is relatively unaffected by other dietary factors. Non-haeme iron, in contrast, is relatively poorly absorbed (usually less than 10% of dietary intake and often under 5%). Its absorption is markedly influenced by an individual's iron status and dietary factors that can either inhibit or enhance it.
There are conflicting reports about the effect of tea on iron absorption but the current recommendations are:
-There is no evidence to suggest that tea drinking should be restricted in
healthy individuals who are not at risk of iron deficiency and are consuming a well balanced, mixed diet.
-People who have a poor iron status should avoid drinking tea with meals and up to at least one hour after the meal. Any adverse effects that tea may have on iron absorption are then likely to be minimised.
-Certain groups are at higher risk of poor iron status (infants and toddlers, teenage girls, premenopausal women and males over 75 years). Based on the published evidence, the higher rates of poor iron status amongst these groups cannot be directly linked to tea drinking. However, it would be prudent to recommend that tea is not drunk with meals or up to one hour after the meal.
Moderate tea drinking (3-4 cups) spread throughout other times of the day is unlikely to have any adverse effect on iron status. The inhibitory effect of tea on iron absorption maybe partially overcome by the simultaneous consumption of animal tissues and Vitamin C.
I hope this answers your query.
It is, however, more important to find the cause of iron deficiency and this requires that you be properly examined and investigated.